To increase capacity of magnetic storage systems, efforts are continually made to increase magnetic recording density. For example, capacity may be increased by increasing track density (i.e., width of data tracks and/or distance between adjacent tracks). However, increased track density results in increased effects of adjacent-track interference (ATI) and far-track interference (FTI). That is, writing data to a particular data track can result in the degradation of signals written to adjacent or event non-adjacent data tracks. Repeated write operations to a track can result in irreversible damage to data written on these other tracks.
To prevent a loss of data, magnetic storage systems maintain in random access memory (RAM) a count of damage incurred by each data track. When that count reaches a predetermine threshold level, the data track is “refreshed” by re-writing data to the data track. However, refresh operations take time and therefore degrade performance. They require an entire data track to be read from the magnetic media, and then re-written to the magnetic media to ensure any damage or errors sustained by the data track are remedied. The time required for a refresh operation is time that cannot be spent on other operations, resulting in a degradation of system performance.
It would therefore be beneficial to prevent initiation of refresh operations until required while maintaining the integrity of data stored to the magnetic media.